Essential evidence on transport safety

Dr Adrian Davis, an expert in the field of transport and health, has produced a series of one-page Essential Evidence summaries that highlight key research of value to transport planners and policymakers. The research is taken from peer-reviewed literature, including specialist journals.

Here’s our round up of the evidence summaries most relevant to professionals involved in child accident prevention.

Road safety

There is safety in numbers for pedestrians and cyclists - the risk of being involved in a motor vehicle collision, per unit of exposure, is lower with higher levels of walking and cycling. A 2003 analysis of data from Europe and the USA on walking and cycling found that motorists appear to adjust their behaviour in the presence of pedestrians and cyclists, which largely controls the increased likelihood of collisions. See 1: Safety in numbers (link opens PDF) for more information.

Danish legislation means that school children must be provided with safe routes to school. Common interventions include reducing traffic speeds and improving signalling at junctions. School route studies often contribute to local road safety plan development, for example by identifying locations where children feel unsafe; this is valuable because the low number of crashes make it impossible to identify ‘black spots’ from casualty data alone. See evidence summary 14: A healthy school journey (link opens PDF) for more information.

Cycling safety

Evidence from countries with high cycling levels suggests that the key to safety is the provision of separate cycling facilities along heavily travelled roads and at intersections, combined with residential street traffic calming. In the Netherlands, major improvements to cycling infrastructure and restricted car use led to a 81% fall in the cyclist fatality rate from 1978-2006, alongside a 36% increase in km cycled per inhabitant. Safer cycling in the Netherlands is not due to widespread use of safety helmets, with fewer than 1% of adult cyclists and only 3–5% of child cyclists wearing helmets. See evidence summary 25: Cycling safety – lessons from the Netherlands, Denmark and Germany (link opens PDF) for more information.

Pedestrian safety

The consequences of child pedestrian crashes extend beyond that of the immediate injury. 23% of all children struck by cars can be expected to experience some psychological impacts, and their parents are at increased risk for psychological symptoms. In an evaluation of Safe Routes to Schools interventions in New York, annual pedestrian injury rates in intervention areas were found to decrease by 33% among school-aged children but remain fairly stable in other age groups. Among school-aged children, 5-9 year olds experienced the largest decline in injuries (42%). See evidence summary 104: Effectiveness of Safe Routes to School programmes (link opens PDF) for more information.

Traffic speeds

A 2007 analysis of public perceptions of anti-social behaviours revealed that speeding traffic is rated as the greatest problem in local communities. A 2003 survey of driving behaviour in Britain revealed that over 80% of drivers support the 30mph speed limit in towns, with a third of drivers viewing the same speed limit as too high for narrow residential streets. See evidence summary 52: Is speeding a ‘real’ anti-social behaviour? (link opens PDF) for more information.

There is little evidence that drivers understand the dangers of speed around child pedestrians and slow down in their presence. Potential interventions include issuing specific guidelines about appropriate speeds, training programmes and advertising campaigns, and speed limit enforcement. See evidence summary 67: Speeds of drivers in the presence of child pedestrians (link opens PDF) for more information.

Use of speed cameras leads to appreciable reductions in speed in the vicinity of the cameras and substantial reductions in collisions and casualties. An RAC Foundation study found that the operation of cameras at over 4,000 sites resulted in around 1,000 fewer people being killed or seriously injured in the year ending March 2004. See evidence summary 97: Effectiveness of speed cameras in preventing road traffic collisions and casualties (link opens PDF) for more information.

Approaches to road safety

The road danger reduction (RDR) approach to road safety aims to reduce danger at source and promote equity and accessibility for non-motorised road users. It takes into account a wide range of safety measures, such as casualty rates, the speed and volume of motorised traffic and the number of trips made using the more vulnerable modes of transport. The RDR approach aims to make drivers aware of their responsibilities to others because of the dangers they pose. Children and young people may particularly benefit from RDR, because their independent mobility has been adversely affected by growth in private motorised transport. See evidence summary 55: Casualty and road danger reduction (link opens PDF) for more information.

Evidence and evaluation

One tool that is commonly used when evaluating road transport interventions is the ‘evidence hierarchy’. This lists a range of study designs ranked in order of validity. However, it is very important to recognise that different types of research question are best answered by different types of study design. Transport planning practitioners should consider how they can make use of the wide range of evidence available and to consider what study designs are most suitable for answering particular types of question. See evidence summary 3: Evidence hierarchy (link opens PDF) for more information.

Parental engagement

A 1995 study in New Zealand found an inverse relationship between the frequency with which parents advocate for child safety and the need for it. The characteristics of parents least likely to take on the advocacy role were found to be the same characteristics that identified groups most at risk of child pedestrian injury. Barriers to advocacy among parents of children at high risk of injury include language and literacy issues, lack of time and suspicion of officialdom. See evidence summary 22: Inverse Care Law (link opens PDF) for more information.

More frequent parental supervision and restricted teen access to a car are associated with reduced likelihood of speeding and increased likelihood of seatbelt use. Parent–teen driving contracts are a potentially important tool for promoting parental management practices. In the USA, research indicates the effectiveness of certain components of Graduated Driver Licensing (GDL) programmes. Delayed ages for permit and provisional licence, increased supervised driving and night-time driving restrictions have resulted in reduced rates of risky driving behaviours, crashes, violations and overall amount of driving. See evidence summary 74: Can parents affect the likelihood of young drivers having accidents? (link opens PDF) for more information.

Collaboration and links to other agendas

Independent mobility appears to be an important independent determinant of weekday physical activity for both boys and girls. Parents may be much more likely to allow their children to have independent mobility if they perceive their environment to be safe and traffic density to be low. See evidence summary 36: Children’s independent mobility (link opens PDF) for more information.

Traffic calming schemes not only create benefits in terms of casualty reduction and reduced traffic danger, but may also be important in improving the physical health of local residents. See evidence summary 54: Health effects of a neighbourhood traffic calming scheme (link opens PDF) for more information.

‘Reticulists’ are individuals who are skilled at working with communication networks, identifying where decisions are made within organisations and finding ways to achieve benefits which cannot be achieved by one organisation or sector alone. These skills are valuable for effective partnership working. See evidence summary 88: Collaboration, sectoral protectionism, and reticulists in public policy (link opens PDF) for more information.